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Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Solving power system problems integrated wind power using improved coyote optimization algorithm
Get PDFYÖK Tez No: 561401Günümüzde endüstri ve teknoloji bazlı gelişmeler göz önüne alındığında talep edilen ve tüketilen enerjide ciddi bir artış durumu söz konusudur. Bu artış enerji sektöründe çeşitli planlamalar yapılması durumunu meydana getirmiştir. Güç sistemleri planlamasında en temel optimizasyon problemlerinin başında Ekonomik Yük Dağıtımı (EYD) ve Optimal Güç Akışı (OGA) problemleri gelmektedir. EYD, gerekli yük talebini karşılamak amacıyla çeşitli kısıtlara bağlı olarak sistem mevcut yükünün üretim birimleri tarafından minimum maliyetiyle karşılanmasıdır. OGA problemi ise, eşitlik ve eşitsizlik sınırlamalarına bağlı kalarak, en iyi kontrol parametrelerin belirlendiği lineer ve konveks olmayan bir optimizasyon problemidir. Günümüzde gerekli olan yük talebini karşılamak amacıyla kullanılan fosil yakıtlar tükenme aşamasında olup, COx, NOx ve SOx gibi gaz salınımları nedeniyle atmosferde sera etkisi oluşturmaktadır. Son zamanlarda artan çevresel farkındalık ve ekonomik faktörlerden dolayı yenilenebilir enerji ve özellikle de rüzgar gücü, güç sistemlerinde daha yaygın bir şekilde kullanılmaya başlanmıştır. Bu çalışmada rüzgar gücü entegreli çeşitli güç sistemleri problemleri ele alınmıştır. Rüzgar hızının doğadaki belirsizliğinden dolayı Weibull Olasılıksal Dağılım Fonksiyonu (ODF) ve Tamamlanmamış Gama Fonksiyonu (TGF) kullanılmıştır. EYD ve OPF problemlerinin çözümünde geçmişte kullanılan klasik matematiksel yöntemler günümüzde yerini sezgisel algoritmalara bırakmıştır. Bu çalışmada bu problemlerin çözümünde kullanılmak üzere sezgisel ve sürü zekasına dayalı bir yöntem olan Kır Kurdu Optimizasyon Algoritması (KKOA)'nın Levy Uçuşu tabanlı geliştirilmesi sağlanmıştır. Geliştirilmiş Kır Kurdu Optimizasyon Algoritması (GKKOA), CEC-2005 problemlerinde test edilmiş ve yapılan geliştirmenin algoritmanın performansında önemli ölçüde artış sağladığı görülmüştür. GKKOA etkili sonuçlar verebilen ve probleme kolay uygulanabilen bir optimizasyon algoritmasıdır. Elde edilen sonuçlar, Parçacık Sürüsü Optimizasyonu (PSO), Genetik Algoritma (GA), Güve Sürüsü Algoritması (GSA) ve Kaos Tabanlı Güve Sürüsü Algoritması (KGSA) ve Kır Kurdu Optimizasyon Algoritması (KKOA) gibi etkili algoritmalar ile karşılaştırıldığında güç sistemleri problemlerinin çözümünde GKKOA'nın daha etkili sonuçlar verdiği açık bir şekilde görülmektedir.Nowadays, considering the developments in industry and technology, it can be seen a serious increase in the energy demanded and consumed. This increase has led to various plans in the energy sector. Economic Load Distribution (ELD) and Optimal Power Flow OPF problems are the most important optimization problems in power systems planning. ELD can described as allocation of the demand among the generating units with minimum costs while meeting the various system constraints. OPF is a nonlinear and non-convex optimization problem which is aim to find the best control parameters while providing the equality and inequality constraints. Today, the fossil fuels used in order to meet the required load demand are in the depletion phase and cause greenhouse effect in the atmosphere due to gas emissions such as COx, NOx and SOx. Recently, renewable energy and especially wind power have become more widely used in power systems due to increasing environmental awareness and economic factors. In this thesis, wind power integrated various power systems problems are handled. Weibull Probability Distribution Function (PDF) and Incomplete Gamma Function Function (IGF) were used because of the uncertainty of wind speed in nature. The classical mathematical methods used in the past to solve EYD and OPF problems have been replaced by heuristic algorithms today. In this thesis, it is provided to improved Coyote Optimization Algorithm (COA) which is a heuristic and swarm intelligence based method to solve problems by using Levy flight method. Improved Coyote Optimization Algorithm (ICOA) has been tested in CEC-2005 problems and it has been seen that the improvement has significantly increased the performance of the algorithm. ICOA is an optimization algorithm that can give effective results and can be applied to the problem easily. According to the results obtained, it is clearly seen that ICOA provides more effective results in the solution of power systems problems compared to effective algorithms such as Particle Swarm Optimization (PSO) and Genetic Algorithm (GA), Moth Swarm Algorithm (MSA) Chaotic Moth Swarm Algorithm (CMSA) and Coyote Optimization Algorithm (COA)
Determination of power system controller parameters using fitness distance balance based social network search algorithm
Get PDFBu tez çalışmasında, modern güç sistemlerinin güvenli bir şekilde çalışmasında kritik bir öneme sahip olan ve geçici durum kararlılık analizi probleminin çözümünde kullanılan denetleyicilerin, en uygun parametrelerinin belirlenmesini sağlamak amacıyla uygunluk-mesafe dengesi (Fitness-Distance Balance, FDB) tabanlı sosyal ağ arama (Social Network Search, SNS) algoritması (FDBSNS) geliştirilmiştir. Bu kapsamda tez çalışması, üç genel aşamadan oluşmaktadır. İlk aşamada, zayıf keşif-sömürü yeteneği ve erken yakınsama problemleri nedeniyle SNS algoritması, FDB seçim yöntemi kullanılarak geliştirilmiştir. FDB yöntemi, SNS algoritmasındaki arama sürecinde çözüm adaylarının uygunluk ve mesafe değerlerini dikkate alarak daha verimli bir şekilde seçilmesini sağlamaktadır. Bu doğrultuda, geliştirilen FDBSNS algoritmasının performansı IEEE CEC 2014 ve CEC 2017 kıyaslama problemleri kullanılarak test edilmiştir. İkinci aşamada, FDBSNS algoritması güç sistemlerinde geçici durum kararlılığının sağlanması amacıyla güç sistemi kararlı kılıcısının (Power System Stabilizer, PSS) en uygun parametrelerinin belirlenmesi problemine uygulanmıştır. Çalışmada, FDBSNS'nin yanı sıra 10 farklı güncel ve etkili rakip Meta-sezgisel Arama (MSA) algoritması kullanılarak PSS parametrelerinin en uygun edeğerleri belirlenmiştir. Sonrasında, belirlenen amaç fonksiyonuna göre elde edilen uygunluk değerleri, çeşitli istatistiksel analiz yöntemleri kullanılarak karşılaştırılmıştır. Ayrıca, FDBSNS'nin etkisi, çeşitli arıza senaryosu durumları için zaman alanı analizleri gerçekleştirilerek WSCC 3-Makineli 9-Baralı ve New England 10-Makineli 39-Baralı test sistemlerinde incelenmiştir. Üçüncü aşamada ise, FDBSNS , güç sistemlerinde geçici durum kararlılığının sağlanması amacıyla TCSC tabanlı denetleyicilerin en uygun parametrelerinin belirlenmesi probleminin çözümünde kullanılmıştır. Problemin çözümünde FDBSNS'nin yanı sıra 11 farklı güncel ve etkili rakip algoritma kullanılarak TCSC tabanlı faz ilerlemeli-faz gerilemeli (Lead- Lag, LL) ve TCSC tabanlı orantılı-integral-türev (Proportional-Integral-Derivative, PID) denetleyicilere ait parametrelerin en uygun değerleri belirlenmiştir. Ayrıca, FDBSNS'nin problemin çözümündeki etkisi tek makineli sonsuz baralı (Single Machine Infinite Bus, SMIB) bir güç sisteminde belirlenen arıza durumu ve farklı yüklenme senaryoları için uygunluk değerleri, istatistiksel analizler ve zaman alanı analizleri açısından incelenmiştir. Elde edilen sonuçlar, geliştirilen FDBSNS'nin kıyaslama problemlerinin çözümünde ve denetleyici parametrelerinin en uygun değerleri elde edilerek geçici durum kararlılığının sağlanması konusunda, rakip algoritmaların tamamına kıyasla üstünlük sağladığını göstermektedir.In this thesis study, in order to determine optimal parameters of the controllers, which are of crucial importance in the safe operation of modern power systems and used in the solution of the transient stability analysis problem, the fitness-distance balance (FDB) based Social Network Search, (SNS) Algorithm (FDBSNS) has been improved. In this context, the thesis study consists of three general stages. In the first stage, the SNS algorithm was developed using the FDB selection method due to its insufficient exploration-exploitation capability and early convergence problems. The FDB method enables the solution candidates to be selected more efficiently by considering the fitness and distance values in the search process in the SNS algorithm. Accordingly, the performance of the improved FDBSNS algorithm was tested using IEEE CEC 2014 and CEC 2017 benchmark problems. In the second stage, the FDBSNS algorithm is applied to the problem of determining the optimal parameters of the Power System Stabilizers (PSS) in order to provide transient stability in power systems. In solving the problem, PSS parameters were optimized by using 10-different up-to-date and effective competitor Meta-heuristic Search (MSA) algorithms in addition to the proposed FDBSNS algorithm. Afterward, the fitness values obtained by MSA algorithms according to the proposed objective function were compared using various statistical analysis methods. In addition, the effect of FDBSNS was tested in the WSCC 3-Machine 9-Bus and New England 10-Machine 39-Bus test systems by conducting time domain analyses for the various fault scenarios. In the third stage, the FDBSNS is used to solve the problem of determining the optimal parameters of TCSC-based Controllers problem in order to provide transient stability in power systems. In the solution of the problem, the parameters of TCSC-based Lead-Lag (LL) and TCSC-based Proportional-Integral-Derivative, (PID) controllers were optimized by using 11 different up-to-date and effective competitor algorithms as well as FDBSNS. In addition, the effect of the FDBSNS on the solution of the problem has been investigated in terms of statistical analyzes and time domain analyses for the fault condition and different loading scenarios determined in a Single Machine Infinite Bus (SMIB) power system. When the results obtained are examined comprehensively, it is seen that the improved FDBSNS provides a superiority to all the competitor algorithms in solving the benchmark problems and in ensuring transient stability by optimizing the controller parameters in power systems
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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